The Rubik's Cube dates to my childhood, when it was for leaving on a desk to be fiddled with — or, for a select few strange birds, for actually solving, sometimes very quickly. At that time, knowing ...
If you suspend a Rubik’s Cube near the corner of a room and shine lights at its exposed faces, it will cast square shadows on two walls and the floor. A real-world Rubik’s Cube has a gadget at its ...
An engineer noted for his ability to visualize three-dimensional structure was having coffee and doughnuts. Before he dropped a sugar cube into his cup, he placed the cube on the table and thought, ...